You can use b'Lure straight out of the dropper bottle which is naturally bright blue. An edible natural blue food is quite rare in nature. That's why b'Lure is so special.

If other ingredients are added that have a higher acidity (like limes or lemons), the colour then changes from blue to purples and pinks depending on surrounding light & the acidity (pH) of the drink or food it is mixed with.

More Acid = More Purple - The colour is blue at pH 8 to pH 4 (if in neutral substances like water, clear spirits or milk). It will change to royal purple at pH 3 and to bright pink at pH 2 (so the more acidic it becomes after adding other ingredients).